

package com.hazelcast.jet.impl.pipeline.transform;

import com.hazelcast.jet.core.ProcessorMetaSupplier;
import com.hazelcast.jet.impl.ProcessorClassLoaderTLHolder;
import com.hazelcast.jet.impl.pipeline.PipelineImpl.Context;
import com.hazelcast.jet.impl.pipeline.Planner;
import com.hazelcast.jet.pipeline.BatchSource;

import javax.annotation.Nonnull;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serial;

import static com.hazelcast.jet.impl.util.Util.doWithClassLoader;
import static java.util.Collections.emptyList;

public class BatchSourceTransform<T> extends AbstractTransform implements BatchSource<T> {

    @Serial
    private static final long serialVersionUID = 1L;

    @Nonnull
    public ProcessorMetaSupplier metaSupplier;
    private boolean isAssignedToStage;

    public BatchSourceTransform(@Nonnull String name, @Nonnull ProcessorMetaSupplier metaSupplier) {
        super(name, emptyList());
        this.metaSupplier = metaSupplier;
    }

    public void onAssignToStage() {
        if (isAssignedToStage) {
            throw new IllegalStateException("Sink " + name() + " was already assigned to a sink stage");
        }
        isAssignedToStage = true;
    }

    @Override
    public void addToDag(Planner p, Context context) {
        determineLocalParallelism(metaSupplier.preferredLocalParallelism(), context, false);
        p.addVertex(this, name(), determinedLocalParallelism(), metaSupplier);
    }

    @Serial
    private void writeObject(ObjectOutputStream out) throws IOException {
        out.writeObject(metaSupplier);
        out.writeBoolean(isAssignedToStage);
    }

    @Serial
    private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
        metaSupplier = doWithClassLoader(ProcessorClassLoaderTLHolder.get(name()), () -> (ProcessorMetaSupplier) in.readObject());
        isAssignedToStage = in.readBoolean();
    }

}
